Usually just using Waze will tip you off there's a deployment in action. You'll see a lot of pins drop in the same area.

Most states will post when they are doing air enforcement in the newspaper. I always google things like "checkpoint" and "air patrol" before I travel into weird states like Louisiana that do more unconventional type traffic work.

If you want to get really sophisticated you can use a PCAS (Portable Collision Avoidance System) you can find those under the aviation electronics. They're a mixed bag in practical use in aircraft but in cars they can orient aircraft flying in a pattern above you. Mine will pin the gas line inspection aircraft when I head out I10 to New Orleans.

Or wait for a bit because soon all aircraft will be required to register their transponder then you can get this goody. If it will allow you to turn off ground proximity warnings it might be the ultimate aircraft tracker. Even state patrols that block their tail numbers from flightaware should be on this system. Then you just look for suspicious pattern flying. But you might need a co-pilot to run it and there will be a learning curve.

Look up "Stratux" on google, it's an open source project that does everything a Stratus can do, but using a cheap Raspberry pi, a couple SDR dongles and a GPS.
Just leaving this here because I've been spending the last week looking into this and I'm playing with ADS-B things...

Look up "Stratux" on google, it's an open source project that does everything a Stratus can do, but using a cheap Raspberry pi, a couple SDR dongles and a GPS.
Just leaving this here because I've been spending the last week looking into this and I'm playing with ADS-B things...

Click to expand...

I saw this when I was doing my PiAware research. It looks cool in that you also get the weather as well. There are a lot of great options out there for ADS-B receivers and the prices are relatively affordable.